Plastic blow molded containers having rigid neck portions are known in the art. Likewise, methods for producing containers and cups that have rims that are flat on top, including those having a rim with a rolled configuration, are also known.
However, in the production of such articles, especially those requiring a means to accept a closure and/or a handling flange, several practical issues are encountered. Such cases typically require the use of increased amounts of material in the upper portion of the container or the addition of complicated processing steps and techniques.
In some applications, a circular foil closure is sealed to the top surface of the rim of the container to protect the contents of the container from contamination and spillage. The seal between the foil and the container must be leak-proof and the contact must be good to resist movement as the products are transported. The integrity of the seal necessitates a high degree of dimensional stability in the rim portion of the container. At the same time, it is also very important that the container can withstand normal axial loading.